Hydraulic resistance brake for rotary members



Nov. 14,1950 R. E. CORNWELL 2, ,540

HYDRAULIC RESISTANCE BRAKE FOR ROTARY MEMBERS Filed Aug. 25, 1949 4 Sheets-Sheet 1 IN VEN TOR. RALPH E. COENWELL 4 QWM H TTOENE Y Nov. 14, 1950 R. E. CORNWELL 2,529,540

HYDRAULIC RESISTANCE BRAKE FOR ROTARY MEMBERS Filed Aug. 25, 1949 4 Sheets-Sheet 2 40 \l I m I INVENTOR.

i1: 5;; BMW E. CORNWELL 50 n y 5 Q 75 76 9M M u :7 A TTORNE Y Nov. 14, 1950' R. E. coRNwELL 2,529,540

HYDRAULIC RESISTANCE BRAKE FOR ROTARY MEMBERS Filed Aug. 25, 1949 4 Sheets-Sheet 3 INVEN TOR.-

E/u PH E. Caleb/WELL flTT OENE Y Patented Nov. 14, 1950 HYDRAULIC RESISTANCE BRAKE FOR ROTARY MEMBER'S Ralph E. Cornwell, La Canada, Calif.

Application August 25, 1949, Serial No. 112,203

9 Claims. (01. 1ss 90) to arotarydriven element, and the same hy-' draulically locked against rotation; which, in

its full released condition renders the rotary element free for rotation with but negligible-fluid era-a; so as to avoid generating excessive heat; and which embodies a rotor holding the main body of hydraulic fluid under the action of cen riiugal force, in a manner to reduce to a neg,- ligible minimum the tendency of fluid to leak from the system when the machine is running with the brake fully released, so that only when pressure is built up in the system by the braking action, or when the machine is atrest, is the need fora fluid-tight system present.

7 The primary object of my present invention is to provide a hydraulic braking mechanism which has all the-advantages of' my patented invention; whichis materially simplified structurally and functionally toproduce a more compact unit of smaller diameter without such projecting parts-as might be damaged or broken off :by road obstructions or lowering of the unit closer to the road as a result of a fiat tire; which em-.

bodies a greatly simplified and exteriorly located by pass valving structure having fewer partiand being much easier to operate; and

Q which enables such heat as is generated; to be much mor easily dissipated bysubjectingthe hydraulic fluid to the action of atmospheric'air or other cooling agent during circulation of the fluid pexteriorly of the unit.

A f-urther' object of mypresent invention isto provide a hydraulic braking mechanism of the above described character which embodies novelfivane structure and im'eans for retaining the'v-anes thereof in a predetermined operating position in oppositionto the action of centrifugal force in tending to shift'the vances from such position.

With these and other objects in view, my invention resides in the combinations, arrangements and functional relationships of elements asset-forth inthe followin specification and particularly pointed out in the appended claims.

In the accompanying drawings,

, Figure 1 is a diametric, axial sectional viewoi one form of hydraulic braking mechanism e hb'odying my invention;

Figure 2 is a transverse sectional View taken on the line 22 of Figure 1 and illustrating the position of the working parts When the brake ir; fully released; 1 I

Figure 3 is a fragmentary sectional view similar to Figure 2, and'illus-trating the positions of the working parts when the brake is partly applied; t

Figure 4 is a transverse sectional view taken 0:: the line ii of Figure 1, and showing the positions of the working parts corresponding to those in Figure 3;

Figure 5 is a fragmentary sectional view taken on the line 5-5 of Figure 4, and showing in f ll lines the position ofa bypass valve when the brake is' fully applied to produce a hydraulic lock;

Figure 6 is a fragmentary sectional View taken on the line 6- 6 of Figure 2;

Figure '7 is a view of he rotor oi the mechanism in side elevation;

Figure 8=is a semi-diagrammatic View of a control device for the hydraulic valves of the braking mechanism; and

Figure 9 is fragmentary sectionalview illus tratinga modified formiof means fer counteracting thefeifect of centrifugal iorceuponthe vanes. f

Referring specifically-to the drawin s, 1"- Y 1-:

vcnt'ion, in its present embodiment comp a statorSand a rotor R, the stator being; a generally cylindrical narrow body i0 secured by fr-s naledin bearings land-i5 in the latter, is a driven shaft or axle 16, which, :in the case ,0;

an automobile, or other vehicle, has fixed to the outer projecting end thereof by a key ii, a. Wheel 18 of which the rotor R is a part.

The rotor; R comprises an annular body 26 1 formed i two halvessecured'together by bolts 21; The. inside diameter of the rotor body is such as to receive the outsidediameter. of the stator body I t with ,a fclose fit therebetween. The rotor includes side plates 22 and .co

acting with the rotor body 26, to enclose" the stator S, the side plate 22 extending from the hub vi i of the Wheel l8 and being secured to the rotor body by bolts 25, whereas the sidepiate 23 is secured to the rotor bodyby'boltsit and has a central openin o receive Lthciiange ita of the axle housing I2, all as clearly shown in Figure 1.

The rotor body 20 has a relatively deep recess 3| co-acting with the periphery of the stator body I to define an annular working chamber W for the hydraulic liquid. At opposite sides of the Working chamber the rotor body is provided with annular sealing ribs 32 and 33 of V-shaped and rectangular cross sections, respectively, which have close fits in annular grooves 34 and 35 of complementary cross sections formed in the stator body I0, as also shown in Figure 1, all to the end of sealing the joint between the stator and rotor bodies against leakage of liquid from the WOlking chamber W. It will also be noted that as the capacity of the working chamber is in the rotor body 20, the liquid filling the chamber will be held by centrifugal force in the rotor during rotation thereof, thus reducing to a minimum the tendency for liquid leakage from the system, and limiting any possible leakage to such times as pressure is developed in the system by a brake application or when the wheel is at rest.

At equally spaced locations circumferentially, the rotor is provided with vanes is of segmental form which are slidably mounted in arcuate slots GI formed in slight protuberances 42 on the periphery of the rotor. This mounting of the vanes enables them to be oscillated in the slots 4| from one extreme position to the other to accordingly dispose one end portion or the other of the vanes in spanning relation to the working chamber and in engagement with the periphery of the stator. Each vane is provided with notches 43 and 44,

either of Which is adapted to be entered by a spring-pressed ball 45 to releasably retain the vane in either extreme position against the tendency of centrifugal force to move the vane to a medial position when the rotor is rotating. In lieu of this latching means to counteract the effect of centrifugal force upon the vanes, there is shown in Figure 9 a modified construction which comprises a weight 55a such as a body of lead or other heavy metal which is fixed in a suitable bore 05b in that portion of each vane 40a which becomes the trailing end portion with respect to the directionof rotation of the rotor, so as to tend to urge the vane to the extreme position shown in this figure, when the vaneis being acted on by centrifugal force.

The stator body I!) is provided with a relatively long and narrow slot opening at the periphery of the body into the working chamber W, and intersected medially between its ends by a transversely extending radial slot 5I also opening at the. periphery of the stator into the working cham her. A main valve 52 in the form of a plate, is

'slidably mounted in the slot 5| and is provided at opposite sides with wings 53 slidable in the slot 50 and having cam surfaces 54-.

In the'fully closed position of the valve 52 wherein the valve spans the working chamber W radially as shown in Figure 3, the cam surfaces 55 extend from a point .of tangency at the periphery'of the stator body to the outer end of the valve, as clearly shown in this figure, for (Bo-action of one cam surface or the other with the vanes 40 in camming one end thereof .and then the other clear of the working chamber so as to enable the rotor to rotate with the main valve 52 maintained in any operating position to fully closed position, as will be later fully described;

The'valve 52 is: actuated by a hydraulic actuating' unit in the stator, which-comprises a pair of cylinders 60 and 6| in which work pistons 62, 63 whose rods 64, 65 are connected at 66, 6'! to the Wings 53 of the valve 52. The cylinders 60, BI are connected at one end by a passage 68 to one end of a master cylinder 69, and are connected at the other end by a passage 70 to the other end of the master cylinder.

Working in the master cylinder 69 is a piston II the rod 12 of which is actuated by a control device designated generally at C (Figure 8). For the present it will suffice to state that actuation of the master piston II in one direction will move the valve 52 from the open or non-operating position shown in Figure 2, to the closed or operating position shown in Figure 3, whereas movement of the piston in the opposite direction will effect reverse movement of the valve, all through the medium of the hydraulic liquid which fills all otherwise unoccupied space in the cylinders 60, BI and 69, and the passages 08 and ID.

The stator body I0 is also provided with independent b y-pass passages I5 and I6 at opposite sides of the slot 50. The outer ends of the passages I5 and 76' open atthe periphery of the stator body into the working chamber W to form pairs of ports 58 and I9 (Figure '7) at opposite sides .of the valve 52, whereas their other ends respectively connect through the flange II a of the axle housing I2 with the ends of an exteriorly located cooling conduit 80 provided with a by-pass valve 8| the rod 82 of which is also actuated by the control device 0.

With the main valve 52 closed as shown in Figure 4 and the by-pass valve 8I open as shown in broken lines in Figure 5, liquid in the working chamber W will be forced to pass around the main valve through the passages I5, I5 and the conduit 85 during rotation of the rotor, as indicated by the arrows in Figure 4.

For the purpose of illustration, the control device C comprises a cam plate I05 reciprocably mounted in a guide I06 and adapted to be manually or otherwise actuated by a rod I01. The cam plate I05 is provided with a cam slot I00 having an active portion I09 and a dwell portion H0, in which works a roller III carried by the rod E2 of the piston II. The cam plate I05 is further provided with a second cam=slot II2 having an active portion H4 and a dwell portion I I5 in which works a roller I I6 carried by the rod 82 of the by-pass valve 8|, for synchronized successive actuation of the piston 'II and valve BI during the operation of the invention which is as follows:

In the position of the cam plate I05 shown in Figure 8, the main valve 52 and the by-pass valve BI are fully open, thus permitting unrestricted rotation of the rotor R, as the vanes 40 merely circulate the liquid in the working chamber W as shown by the arrows in Figure 2, with but negligible fluid drag.

.However, upon moving the cam plate I05 to the left, the piston M will first be moved in its cylinder 69 to initiate closing movement of the valve '52 fro-m its fully open or non-operating position, and thus restrict circulation of the liquid in the working chamber W by the vanes 45, which latter are successively oscillated by one or the other of the cam surfaces 54 according as the rotor is rotating in one direction or the other, so as to pass by the valve 52 and then occupy the extreme position shown in Figures 2 and 4. This restricted circulation of the liquid forces part thereof through the restricting by-pass ports I8, I9, passages 15, I6 and cooling conduit 80,

1 to {the end that a braking action upon the rotor will be developed and will be increased as further termed a service application, be insuificient,

continued movement of the cam plate 15 to the a left will maintain the main valve 5-2 fully closed, .while closing movement of the by-pass valve 81 Willbe initiated, to thus further restrict the flow ofliquidthroughthe by-pass ports 18, I9, passages l5, l6 and cooling conduittll; and hence increase the braking action upon the rotor, until in the fully closed positions of the valves 52 and 8| all circulation of 'liquid will cease, so as to form a hydraulic lock upon the rotor against rotation thereof.

By now moving the cam plate N15 to the right, the reverse actuation of the valves 52 andlll will be successively effected to release the brake as smoothly as it was previously applied. 7 It will be evident that by, rapidly actuating the valve I05 tothe left from its original position shown in Figure 8, a maximum or emergency application of thejbrake can be smoothly and powerfully effected by the closing of the valves 52 and 8|,

and the rotor hydraulically locked against rotation.

Furthermore, it will be 'clear. that by the prov v vision of the simplified liquid by-pass system and the; disposition of the cooling conduit 88 exteriorly of the machine so as to be subjected to the coolingfaction of atmospheric air, such heat as is generated. by a brake application willbe rapidly and effectively dissipated, thus insuring the working parts and thefluid against overheating.

I claimz 1. Hydraulic braking mechanism comprising:

' a stator; an annular rotor-receiving the stator and co-acting therewithto' define ltherebetween anannular working chamber for liquid; jsegmental shaped vanes mountedv inthe rotor for oscillatory movement from one extreme position to another to dispose one end portionor the other .thereo'fdn spanning relation to theworking chamber'fo'r circulation of the liquid in the chamher by the vanes when the[rotor-isr'otating'; a main valve mounted inthe'stator for}mo'v.e ment firorna non-operating position to an operating fiosition in the working chamber so asz to oppose circulation of liquid in the latter by the varies; said valvehaving afcam surface extend,-

irig circumferentially; of the stator andbywhich of the mechanismso as to be exposed to thecool the vanes are'oscillated from one extremeposi tionto the other so as to permitttlievanes to pass the 'valve whenfthe latter occupies'an operating position; and meansby which a restricted circulation of liquid in the working chamber can be effectedaround .the-,valve when in operating position; so-as 'to produced, braking action upon the rotor. v

2. Hydraulic braking mechanism comprising:

. a-stator; an annular rotor receiving the stator and 'co-acting therewith to definetherebetween an annular working chamber for liquid; segmental shaped vanes mounted in the rotor for oscillatory movement from one extreme position to another to dispose one end portion or the other fromanOn-operating-pbSitiofi to an operating 6; position in the working chamber so" aszto oppose circulation of liquid in the latter by the vanes; said valve having a cam surface extendingfcir cumferentially of the stator and by which the vanes are oscillated from oneextreme: position to the other so. as to permit the vanes to pass the valve when the latter occupies, an operating position; the stator having a by-pass communi cating with said working chamber at opposite sides of said valve; a cooling conduit extending exteriorly of the mechanism so as to be exposed to the cooling eiTect of air or other means; said conduit being connected to said 'by-pass'so'as to form aby-pass circuit for the liquid; means for actuating said main valve; a by-pass valve by which circulation or liquid through said-bypass circuit can be varied to increase to braking action upon the rotor to the maximum of a 'hydraulic lock thereupon; and means for actuating her by the vanes when the rotor is rotating; la-

main valve mounted in the stator for movement from a non-operating position to an operating position in the working chamber so as to oppose circulation of liquid in the latter by, the vanes;

' said valve having a cam surface extending circumferentially of the stator and by .which the vanes, are oscillated from oneextreme position to the other so as to permit the vanes to 'pass the valve when the latter occupies an operating position; the stator having a by-pass communicating with said working chamber at opposite sides of said valve; acooling conduit extending exteriorly ing efie'ct of air orother meansfsaid conduit being connected tosaid by-pass so as to form a by-pass circuit for the liquid; a by-pass valve in said cooling conduit by which circulation of liquid through said by-pass circuit can be varied to increase the brakingaction upon the rotorto the maximum of a hydraulic lockthereuponpand I control means for actuating the mainand bybass valves in successive order to first move 'thermain valve fr'o'm' non-operating position to operating position, and then move the by-pass valve'frorn open position to closed positionwithrespectfto said by-pass circuit A 4. Hydraulic braking mechanism comprisingi a stator; a rotor co-actingwith the stator to define therebetween an annular working'jchamber for a liquid; therotor having arcuate slots whose lengths are in'parallelism with the plane of rotation of the rotor; segmental vanesmounted in said slots for oscillatory movement from one extreme position to another to accordingly project one end portion or the other of said vanes'into the working chamber for the circulation of liquid therein by the vanes when the rotor isjrotat'e'd'; 'a valve mounted for movement from a non-operating position to an operating position in the working chamber so as to oppose circulation of liquid therein by the vanes means for moving the vanes clear of the valve when the latter is in operating position, so as'to enable the 'vanesfto pass the valve; and means r s mausg the i ,i a;

5. Hydraulic braking mechanism comprising: a stator; a rotor ,co-acting with the stator to define therebetween an annular working chamber for aliquid; the rotor having arcuate slots whose lengths are in parallelism with the plane of rotation of the rotor; segmental vanes mounted in said slots for oscillatory movement from one extreme position to another to accordingly project one end portion or the other of said vanes into the working chamber for the circulation of liquid therein by the vanes when the rotor is rotated; a valve mounted for movement from a non-operating position to an operating position in the working chamber so as to oppose circulation of liquid therein by the vanes; means for moving the vanes clear of the valve when the latter is in operating position, so as to enable the vanes to pass the valve; means defining a by-pass through which restricted circulation of liquid in the working chamber may be effected past the valve when in an operating position, so as to produce a braking action upon the rotor; and means for actuating the valve.

6. Hydraulic braking mechanism comprising; a stator; a rotor co-acting with the stator to define therebetween an annular working chamber for a liquid; the rotor having arcuate slots whose lengths are in parallelism with the plane of rotation of the rotor; segmental vanes mounted in said slots for oscillatory movement from one extreme position to another to accordingly project one end portion or the other of said vanes into the working chamber forthe circulation of liquid therein by the vanes when the rotor is rotated; a valve mounted formovement from a non-operating position to an operating position in the working chamber so as to oppose circulation of liquid therein by the vanes; means for moving the vanes clear of the valve when the latter is in operating position, so as to enable'the vanes to pass the valve; the stator having by-pass ports respectively communicating with the working chamber at'opposite sides of said valve; means including a cooling conduit extending exteriorly of the mechanism for exposure to the air or other cooling means, by which saidby-pass ports are connected to define a bypass liquid circuit; a by-pass valve inthe, last means for controlling said by-pass circuit; and means for actuating the first said valve and said by-pass valve in successive order. f V 7. Hydraulic braking mechanism comprising; a stator; an annular rotor receiving the stator and co-acting therewith to define therebetween an annular working chamber for liquid; the rotor having arcuate slots whose lengths are in paralverse slotto occupy a non-operating position therein and operating positions in the working chamber; means carried by the stator, co -acting with the vanes to move the latter clear of the valve whenin an operating position, so as to enable the vanes to pass the valve; and means for actuating the valve;

8. Hydraulic braking mechanism comprising: a stator; an annular rotor receiving the stator and co-acting therewith to define therebetween an annular working chamber for liquid; the rotor having arcuate slots whose lengths are in parallelism with the plane of rotation of the rotor; segmental vanes mounted in said slots for oscillatory movement from one extreme position to another to accordingly project one end portion or the other of said vanes into the working chamber for circulation of'liquid therein by the vanes when the rotor is rotating; the periphery of the stator having acircumferentiall extending slot and a transverse slot in intersecting relation, with both slots opening into the working chamber; a valve reciprocably mounted in said transverse slot to occupy. a non-operating position therein and operating positions in the working chamber; means carried by the stator, co-acting with the vanes to move the latter clear of the valve when in operating position, so as to enable the vanes to pass the valve; the stator having by-pass ports respectively communicating with the working chamber at opposite sides of said valve; means including a cooling conduit extending exteriorly to the mechanism for exposure to the air or other means, by which said by-pass ports are connected to define a by-pass liquid circuit; a by-pass valve in the last means for controlling said by-pass circuit; and means for actuating the first said valve and said by-pass valve in successive order.

9. Hydraulic braking mechanism comprising: a stator; an annular rotor receiving the stator and co-acting therewith to define therebetween an annular working chamber for liquid; the rotor having arcuate slots whose lengths are in parallelism with the plane of rotation of the rotor; segmental vanes mounted in said slots for oscillatory movement from one extreme position to another to accordingly project one end portion or the other of said vanes into the working chamber for circulation of liquid therein by the vanes when the rotor is rotating; the periphery of the stator having a circumferentially extending slot and a outer end of said valve to a point of tangency r with the periphery of the stator when the valve RALPH E. CORNWELL.

REFERENCES CITED The following references are of record in the file of this patent1- UNITED STATES PATENTS 1,501,444 English et al July 15, 1924 2,492,868 Johnson Dec. 27, 1949 FOREIGN PATENTS Number Country Date 509,953 Great-Britain July 25, 1939 512,389 Great Britain Sept. 1, 1939 

